The present disclosure relates to a vision-based system and method for making a traffic regulation violation decision regarding vehicle activity during a stop light signal. The system automatically processes evidentiary images to discriminate between violating vehicles that run a red light and/or stop signal and non-violating vehicles that abruptly stop. However, the present disclosure is amenable to other like applications.
Red Light Camera Systems (RLCS) are traffic regulation enforcement systems that detect and identify vehicles that enter an intersection against a red traffic light and, therefore, are in violation of a traffic regulation. These systems can detect the violating vehicles by identifying license plate numbers and/or the make and model of the vehicles from photographs captured by red light cameras. A citation is then issued to the owner of the vehicle identified in a photograph.
In more specific detail, FIG. 1 shows how an existing RLCS system operates in the PRIOR ART. An enforcement camera 10 is installed in a protective metal box attached to a pole 12 at an intersection. To measure vehicle speed, two closely spaced induction loops (“sensors 14A, 14B”) are embedded in the pavement near the stop line 16. When a vehicle activates both sensors within a predetermined time threshold, the sensors trigger the cameras 10, 18 to capture the event as a series of photographs or a video clip, which shows the vehicle 20 as it enters and proceeds through the intersection on a red light signal 22.
Existing systems generate a number of false detections, which can result in the issuance of erroneous tickets. These false detections mainly result from vehicles that abruptly stop at the stop line after triggering the sensors 14A, 14B within the predetermined time threshold. These systems furthermore require a law enforcement official review the photographs to determine if a violation occurred. This time consuming task also results in a significant number of the violations being rejected as false detections.
An improved system and method is desired which automatically detects non-violating vehicles, which are falsely identified as violating vehicles in the existing system. A system and method are desired which discriminates between violating and non-violating vehicles using evidentiary images.